A detained German terrorist told authorities that Chancellor Angela Merkel can expect an Islamic blitzkrieg from returning fighters.

Lawyers for a disillusioned member of the Islamic State group say the man, known only as Harry S, wants to “come clean.” The 27-year-old from Bremen told Der Spiegel that he “saw it all” and wants to talk. He is the first terrorist to help intelligence officials piece together the fate of German-speaking jihadists Mohamed Mahmoud and Berlin rapper Denis Cusper, known as “Deso Dogg.”

Harry S, who was radicalized after meeting a Salafist René Marc S (known as the Emir of Gröpelingen), during a prison stint in 2010, said he spent three months in ISIS-controlled territory before returning home in July. Authorities say he also carried the ISIS flag in an execution video released by the Sunni terror group.

“He is a lackey who allowed himself to be misled by the propaganda of ISIS and who misled himself,” the terrorist’s lawyer, Udo Würtz, told the magazine Wednesday.

Harry S said he was twice approached by ISIS members in the spring to conduct terror attacks inside Germany, but told them he was not ready. He fled Syria in the middle of the night after months of witnessing executions.

“I walked and walked” the terrorist said of his trek to Turkey. Der Spiegel said that much of Harry S’s testimony has been confirmed by security officials with access to other terror suspects.

The terrorist’s story comes on the heels of reports by Hans-Georg Maasen, a federal police chief, that nearly 8,000 ISIS fighters have infiltrated Germany through its refugee program. Merkel was ironically crowned Time magazine’s 2015 “Person of the Year” on Dec. 9 for her willingness to embrace nearly 1 million refugees from the region.

“For asking more of her country than most politicians would dare, for standing firm against tyranny as well as expedience and for providing steadfast moral leadership in a world where it is in short supply, Angela Merkel is Time’s Person of the Year,” Managing Editor Nancy Gibbs wrote, WND reported.

German intelligence officials not only must deal with returning terrorists, but they also say incoming refugees are a magnet for radicals.

“They start by saying, ‘We will help you live your faith,'” Torsten Voss, the head of the German domestic intelligence agency’s Hamburg branch, told the Wall Street Journal Nov. 28. “The Islamist area comes later – that is, of course, their goal.”

Intelligence officials say German mosques are seeing attendance spikes of up to 200 people.

Merkel appears to have realized the national security threat posed by Muslim refugees. She told a German broadcaster on Sunday that she wanted to “drastically decrease” the number of migrants entering the country, Reuters reported.

ISIS has openly stated that it plans to use U.S. President Obama’s Syrian refugee program as a Trojan horse. Homeland Security Secretary Jeh Johnson said Wednesday that it was possible for the terror network to “exploit” the system, WND reported.

Obama, however, still plans to accept 10,000 Syrian refugees over the next year.

“ISIL does not speak for Islam. They are thugs and killers, part of a cult of death. They account for a tiny fraction of more than one billion Muslims around the world,” Obama said while speaking Thursday at the National Counterterrorism Center in Tysons Corner, Virginia, WND reported.

German Chancellor Angela Merkel was deemed Time magazine’s 2015 “Person of the Year” for her handling of the Syrian refugee crisis.